Upper slewing body and operating machine having the same

ABSTRACT

An upper frame has a bottom plate, a pair of vertical plates that are provided to stand on the bottom plate so as to face each other in a right-left direction, and a left side frame configuring a part of a rim part of the upper frame. An attachment is supported on a support parts provided in front of the slewing bearing in vertical plates. A left vertical plate has a rear curved part, behind the support part, which is curved forming a convex shape directed toward an opposite side of a right vertical plate in a planar view. The upper slewing body further has a first coupling member for coupling the left side frame and the left vertical plate to each other so as to prevent the left vertical plate from being deformed in a direction in which the rear curved part approaches the right vertical plate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an upper frame of an operating machineincluding a hydraulic shovel and crane.

2. Description of the Background Art

An operating machine provided with a lower propelling body and an upperslewing body mounted on the lower propelling body has conventionallybeen known. The upper slewing body has an upper frame supported on thelower propelling body so as to be able to slew, as well as anattachment, cab, machinery room, counterweight and the like that areprovided on the upper frame.

The attachment includes a boom and arm that are attached to the upperframe in a displaceable manner. The boom and the arm are driven by ahydraulic actuator. The attachment is installed at a front portion ofthe upper frame. On the other hand, at a rear portion of the upperframe, a heavy counterweight is installed in order to keep the balancein a front-back direction by weighting against the load applied to thefront part of the upper frame by the attachment.

Specifically, the upper frame has a bottom plate supported on the lowerpropelling body and a pair of vertical plates provided to stand on thebottom plate in a manner as to face each other in a right-left directionand extend in the front-back direction. The pair of vertical platesfunctions as a strength member for steadily supporting the attachmentand the counterweight. Specifically, the attachment is attached to afront part of each vertical plate and the counterweight is attached to arear part of each vertical plate.

When the distances between a center of slewing and the vertical platesare different from each other, the center of gravity of thecounterweight leans toward one of the vertical plates. Consequently, thecounterweight vibrates during traveling or an excavation operation ofthe operating machine, causing a large vibration in the right-leftdirection of the counterweight, which is called “rolling vibration.”

Japanese Patent Application Publication No. 2006-328764 (referred to as“Patent Document” hereinafter), for example, discloses a constructionmachinery for reducing the rolling vibration of a counterweight. Morespecifically, right and left vertical plates that are bent at the middleare provided in the operating machine described in Patent Document, in amanner that the interval between the rear sections of the right and leftvertical plates is wider than the interval between the front sections ofthe right and left vertical plates.

FIG. 9 is a schematic view in which an upper frame (a slewing frame) 101described in Patent Document is viewed from diagonally underneath. Theupper frame has an attaching part 102 provided on each vertical plateand for allowing an attachment to attach, and a slewing bearing 103 forconnecting the upper frame 101 and a lower propelling body, not shown,to each other in a turnable manner. The attaching part 102 is located onthe inside of the slewing bearing 103 in a planar view. Therefore, evenwhen the load applied to the attaching part 102 changes significantly asa result of an operation of the attachment, the lower propelling bodycan reliably receive this load. As a result, the attachment can besupported steadily.

Sometimes, however, the attaching part of the attachment is providedoutside the slewing bearing in a manner as to protrude forward from theupper frame. In this case, a front part of the upper frame swings easilyvertically around the slewing bearing as the load applied to theattaching part fluctuates, making the support of the attachmentunstable.

Especially when the vertical plates are curved significantly in theright-left direction in the upper frame described in Patent Document,the vertical plates are easily deformed so as to expand the curvedsections thereof. This eventually causes the upper frame to swing easilyvertically as described above, making the support of the attachment moreunstable.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an upper slewing bodycapable of steadily supporting an attachment, and an operating machinehaving this upper slewing body.

In order to achieve the object described above, the present inventionprovides an upper slewing body that is provided on a lower propellingbody of an operating machine so as to be able to slew, the upper slewingbody comprising: an upper frame that has a bottom plate that issupported on the lower propelling body via a slewing bearing so as to beable to slew, first and second vertical plates that are provided tostand on the bottom plate so as to face each other in a right-leftdirection and to extend in a front-back direction, and a side framefixed to the bottom plate and configuring a part of a rim part of theupper frame, the vertical plates each having a support part located infront of the slewing bearing; and an attachment that is supported on thesupport parts of the vertical plates so as to be able to rise and fall,wherein the first vertical plate has a curved part, behind the supportpart, which is curved to form a convex shape directed toward an oppositeside of the second vertical plate in a planar view, and the upperslewing body further comprises a first coupling member for coupling theside frame and the first vertical plate to each other so as to preventthe first vertical plate from being deformed in a direction in which thecurved part approaches the second vertical plate.

The present invention also provides an operating machine that has theupper slewing body described above and a lower propelling body thatsupports the upper slewing body via the slewing bearing so as to allowthe upper slewing body to slew.

According to the present invention, the attachment can be supportedsteadily by effectively preventing deformation of the vertical plates,even when the support part of the attachment is located in front of theslewing bearing and the vertical plates are curved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a hydraulic shovel according to an embodimentof the present invention.

FIG. 2 is a schematic plan view of an upper frame of the hydraulicshovel shown in FIG. 1.

FIG. 3 is a schematic perspective view of the upper frame shown in FIG.2.

FIG. 4 is a cross-sectional diagram taken along IV-IV in FIG. 2.

FIG. 5 is a schematic perspective view in which the upper frame shown inFIG. 2 is viewed from below.

FIG. 6 is a schematic side view of the hydraulic shovel, forillustrating how a support part swings.

FIG. 7 is a plan view for explaining functions of a first couplingmember.

FIG. 8 is a schematic view showing a modification of the presentinvention.

FIG. 9 is a schematic perspective view showing an upper frame of aconventional operating machine.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

An embodiment of the present invention is described hereinafter withreference to the accompanying drawings. The following embodiment ismerely an example embodying the present invention and is not to limitthe technical scope of the present invention.

FIG. 1 shows a hydraulic shovel 1 (an example of an operating machine)according to the embodiment of the present invention. The hydraulicshovel 1 has a crawler-type lower propelling body 2 and an upper slewingbody 3 provided on the lower propelling body 2 so as to be able to slewaround a slewing axis A. The hydraulic shovel 1 according to the presentembodiment has a dozer 2 a provided in front of the lower propellingbody 2 for pushing sediments and the like.

The following description is based on the perspective of an operatorsitting in a driver's seat of a cab 6. Each of the drawings shows arrowsindicating the front, rear, upper, lower, right, and left.

The upper slewing body 3 has an upper frame 5 supported on the lowerpropelling body 2, and the cab 6, a machinery room 7, a counterweight 8,an attachment 9, an engine 11 (see FIG. 2), and a slewing motor 12 (seeFIG. 2) that are provided on the upper frame 5.

The attachment 9 is attached to a front part of the upper frame 5.Specifically, the attachment 9 has a boom 9 a having a base end partattached to the upper frame 5 in a manner as to be able to rise andfall, an arm 9 b having a base end part attached swingably to a tip endpart of the boom 9 a, and a bucket 9 c attached swingably to a tip endpart of the arm 9 b. The attachment 9 further has a hydraulic cylinder 9d for causing the boom 9 a to rise and fall with respect to the upperframe 5, a hydraulic cylinder 9 e for causing the arm 9 b to swing withrespect to the boom 9 a, and a hydraulic cylinder 9 f for causing thebucket 9 c to swing with respect to the arm 9 b. The attachment 9 isdisplaced when the hydraulic cylinders 9 d to 9 f are supplied with anddischarge pressure oil.

The cab 6 is provided on the left side of the attachment 9 in the frontpart of the upper frame 5.

The counterweight 8 keeps the balance in a front-back direction byweighing against the load applied to the front part of the upper frame 5by the attachment 9. Specifically, the counterweight 8 is provided in arear part of the upper frame 5. The counterweight 8 of the presentembodiment also plays the role of a rear part cover in the machineryroom 7.

As shown in FIGS. 2 and 3, the machinery room 7 is provided over therange from a right front part of the upper frame 5 to the rear part ofthe same. Various devices and a tank are closely provided in themachinery room 7. For example, the engine 11 is provided in the rearpart of the upper frame 5, with its drive shaft disposed along theright-left direction. The slewing motor 12 is provided in the vicinityof the slewing axis A of the upper frame 5.

The upper frame 5 is a support member of structurally improved strengthand rigidity. The upper frame 5 has a substantially rectangular shape,when viewed planarly. Specifically, the upper frame 5 includes a bottomplate 21 supported on the lower propelling body 2 so as to be able toslew, a slewing bearing 30 provided on a lower surface of the bottomplate 21, a pair of right and left vertical plates 22 (right verticalplate 22R, left vertical plate 22L) provided to stand on the bottomplate 21 in a manner as to face each other in the right-left directionand extend in the front-back direction, a front frame 24 and a pair ofright and left side frames 25 (right side frame 25R, left side frame25L) that configure parts of a rim of the upper frame 5, a plurality ofbeams 23 connecting each of the vertical plates 22 and each of the sideframes 25 to each other, a reinforcing plate 26 for coupling thevertical plates 22 to each other, and a first coupling member 40provided between the left vertical plate 22L and the left side frame25L. Note that each drawing shows a simplified structure of the upperframe 5, for convenience.

The bottom plate 21 configures a bottom surface of the upper frame 5.Specifically, the bottom plate 21 is a metal plate with a relativelylarge thickness, which is disposed substantially horizontally.

The vertical plates 22 are separated from each other in the right-leftdirection. In this state a lower end part of each vertical plate 22 iswelded to an upper surface of the bottom plate 21. Each of the verticalplates 22 is a metal plate with a relatively large thickness. Supportparts 22 a for supporting the attachment 9 are provided in front of theslewing bearing 30 in each vertical plate 22, the slewing bearing 30being described hereinafter. More specifically, the vertical plates 22have the support parts 22 a protruding forward from the front frame 24and beam parts 22 b extending rearward from the support parts 22 a.

The support parts 22 a are formed to be taller than the beam parts 22 b.Specifically, each of the support parts 22 a is formed into a trapezoidor triangle, when viewed laterally. The right and left support parts 22a are disposed parallel to each other. The attachment 9 is attached tothe support parts 22 a and disposed between the support parts 22 a.Specifically, the boom 9 a and hydraulic cylinder 9 d are pivotallysupported so as to be able to turn, by two pins inserted into axis holesformed in the support parts 22 a respectively.

The beams 22 b are formed into band plates of substantially the sameheight. The planar shapes of the right and left beam parts 22 b, on theother hand, vary depending on the arrangement of the equipment includingthe slewing motor 12 and the engine 11. Specifically, the beam part 22 bof the right vertical plate 22R (an example of a second vertical plate)extends almost linearly from a front end to a rear end. More concretely,the beam part 22 b of the right vertical plate 22R has a front partextending from the support part 22 a to a position behind the frontframe 24, an inclined section that is inclined slightly to the right,from the front part to the rear part, and a section that extendsrearward from a rear end of this inclined section.

On the other hand, the beam part 22 b of the left vertical plate 22 (anexample of a first vertical plate) is greatly bent in the right-leftdirection at two sections in the middle. Specifically, the beam part 22b of the left vertical plate 22L has a front part extending from thesupport part 22 a to a position behind the front frame 24, an inclinedpart (an example of a curved front part) 32 that extends rearward from arear end part of the abovementioned front part in a manner that theinclined part becomes distant from the right vertical plate 22R towardthe rear direction, and a parallel part (an example of a curved rearpart) 33 that extends from the inclined part 32 so as to besubstantially parallel (rearward) to the right vertical plate 22R. Inother words, a front curved part 34 in front of the inclined part 32 anda rear curved part 35 behind the inclined part 32 are formed in the beampart 22 b of the left vertical plate 22L. The rear curved part 35 behindthe support part 22 a is formed by bending the left vertical plate 22Linto a convex shape directed toward an opposite side of the rightvertical plate 22R in a planar view. The parallel part 33 extendsrearward from the rear curved part 35, and the inclined part 32 extendsforward from the rear curved part 35 in a manner that the inclined part32 comes closer to the right vertical plate 22R toward the frontdirection.

The front curved part 34 is formed by bending the left vertical plate22L into a convex shape directed (projecting) to the right. The rearcurved part 35, on the other hand, is formed by bending the leftvertical plate 22L into a convex shape directed to the left (to theopposite side of the right vertical plate 22R). The inclined part 32 ofthe left vertical plate 22L is curved at an inclination angle θ withrespect to the parallel part 33 in the rear curved part 35. In thepresent embodiment, the inclination angle θ is set at 20° or greater.

The reinforcing plate 26 is for coupling the vertical plates 22 to eachother in order to improve the rigidity of each vertical plate 22.Specifically, the reinforcing plate 26 has a third coupling member 26 acoupling inner side surfaces of front end parts of the support parts 22a each other, and a second coupling member 26 b coupling the verticalplates 22 each other across the range from rear end parts of the supportparts 22 a to front end parts of the beam parts 22 b. The secondcoupling member 26 b prevents the left vertical plate 22L from beingdeformed in a direction in which the rear curved part 35 approaches theright vertical plate 22R and a direction in which the rear curved plate35 separates from the right vertical plate 22R. Specifically, the secondcoupling member 26 b is for coupling the right vertical plate 22R to theinclined part 32 of the left vertical plate 22L and a range in front ofthe inclined part 32. A lower surface of the second coupling member 26 bis welded to upper surfaces of the vertical plates 22. Note that therear curved part 35 is disposed behind the second coupling member 26 b.

The front frame 24 and the right and left side frames 25 each configurea part of a rim part of the upper frame 5. Specifically, the front frame24 configures a part of a front edge part of the upper frame 5. The sideframes 25 configure right and left frames of the upper frame 5respectively. The frames 24 and 25 are metal processed products.

The front frame 24 has a pair of right and left front frame pieces 24 a.The front frame pieces 24 a extend from outer side surfaces of the rightand left vertical plates 22 (the front end parts of the beam parts 22 b)in opposite directions along the right-left direction.

The right and left side frames 25 extend in the front-rear direction soas to be substantially parallel to each other on the outside of therespective vertical plates 22. Moreover, front end parts of the sideframes 25 are joined (fixed) to the front frame 24. Specifically, thefront end part of the right side frame 25R is joined to a right end partof the front frame piece 24 a on the right side. The front end part ofthe left side frame 25L is joined to a left end part of the front framepiece 24 a on the left side. Rear ends of the side frames 25, on theother hand, are joined (fixed) to the bottom plate 21 via the beams 23.In other words, the side frames 25 are integrated with the bottom plate21 via the front frame 24 and the beams 23. In addition, the side frames25 have high rigidity. Specifically, the right and left side frames 25each have a closed cross section in the shape of an alphabet letter D,as shown in FIG. 4. In other words, each of the side frames 25 is formedby a tubular member that has a circumferential wall provided in a rangeof the entire circumference around an axis in a longitudinal directionof each side frame. In addition, the front frame 24 and each of the sideframes 25 are formed to be taller than the beam parts 22 b locatedwithin the frames 24, 25. A gap for installing electric wires and hosesetc. can be formed above the beam parts 22 b by making the frames 24, 25taller than the beam parts 22 b.

The plurality of beams 23 are members of relatively high rigidity. Eachof the beams 23 couples vertical plate 22 and side frame 25 each otherin order to structurally reinforce the upper frame 5. Specifically, eachof the beams 23, made from a metal plate with a relatively largethickness, couples inner side surfaces of the right and left verticalplates 22 each other. Further, a beam 23 that is formed by bending ametal plate is provided between the right vertical plate 22R and theright side frame 25R so as to couple the right vertical plate 22R andthe right side frame 25R each other. As described above, a beam 23, madefrom a metal plate with a relatively large thickness, is providedbetween the left vertical plate 22L and the left side frame 25L tocouple the left vertical plate 22L and the left side frame 25L. Althoughnot shown, brackets for supporting the various types of equipment on theupper frame 5 are attached directly or indirectly to the beams 23.

FIG. 5 is a schematic perspective view in which the upper frame 5 isviewed from below.

The slewing bearing 30 is provided for allowing the lower propellingbody 2 to support the bottom plate 21, so as to be able to slew aroundthe slewing axis A. Specifically, the slewing bearing 30 is provided ina front part of the lower surface of the bottom plate 21. An inner partof the slewing bearing 30 in the upper frame 5 is supported fromunderneath by the slewing bearing 30 over the entire circumferencearound the slewing axis A, and therefore has extremely high rigidity.For this reason, the attachment 9 that is applied with a greatlyfluctuating load is generally supported on the inside or in the vicinityof the slewing bearing 30. In this case, the attachment 9 can besteadily supported on the upper frame 5.

In the hydraulic shovel 1 according to the present embodiment, however,the support parts 22 a supporting the attachment 9 are disposed in frontof and away from the slewing bearing 30. Thus, there is a possibilitythat the support parts 22 a (the front part of the upper frame 5) swingvertically around the slewing bearing 30 in response to a change in theload applied from the attachment 9, as shown by solid lines and virtuallines in FIG. 6.

Particularly, in the hydraulic shovel 1 according to the presentembodiment, the left vertical plate 22L that functions as a reinforcingmember for supporting the attachment 9 is curved significantly in theright-left direction. This might deform an upper part of the leftvertical plate 22L such that the curved part 35 expands in thefront-back direction (the direction in which the rear curved part 35approaches the right vertical plate 22R), as shown by virtual lines inFIG. 7. As a result, the support parts 22 a swing vertically, moreeasily.

The hydraulic shovel 1 according to the present invention, therefore,has the first coupling member 40 that is fixed to the left side frame25L and the left vertical plate 22L and disposed between the leftvertical plate 22L and the left side frame 25L. Specifically, the firstcoupling member 40 couples the left side frame 25L to a section in theleft vertical plate 22L that is behind and in the vicinity of the rearcurved part 35. In other words, the first coupling member 40 is weldedto a front end part of the parallel part 33 of the left vertical plate22L, so as to be substantially perpendicular to the parallel part 33. Aright end part of the first coupling member 40 is butt-welded to a leftside surface of the front end part of the parallel part 33 of the leftvertical plate 22L. A left end part of the first coupling member 40, onthe other hand, is welded to a circumferential wall of the left sideframe 25L, so as to be substantially perpendicular to a right sidesurface of the left side frame 25L. Furthermore, the first couplingmember 40 extends along the right-left direction in order to becomestrong against a tensile force along the right-left direction and isconfigured by a metal plate that is relatively thin in the front-backdirection.

Coupling the left vertical plate 22L and the left side frame 25L to eachother by using the first coupling member 40 can prevent the leftvertical plate 22L from being deformed in the direction in which therear curved part 35 approaches the right vertical plate 22R.Specifically, as shown in FIG. 7, the load applied from the attachment 9acts on the inclined part 22 b of the left vertical plate 22L, mainly asa tensile force shown by the white arrow. In the present embodiment, thefirst coupling member 40 and the left side frame 25L restrict therightward movement of the left vertical plate 22L. Therefore, a reactionforce for canceling out a component along the right-left direction ofthe tensile force is generated, as shown by the black arrow, in thefirst coupling member 40 coupling the left side frame 25L and the leftvertical plate 22L to each other. Consequently, the first couplingmember 40 and the left side frame 25L inhibit the left vertical plate22L from being deformed. Therefore, the swinging motion of the supportparts 22 a can be prevented effectively.

On the other hand, when the load applied from the attachment 9 acts onthe inclined part 22 b as a compression force in a direction opposite tothe direction of the white arrow shown in FIG. 7, the first couplingmember 40 and the left side frame 25L prevent the left vertical plate22L from being deformed in the direction in which the rear curved part35 separates from the right vertical plate 22R. Specifically, in thepresent embodiment, the first coupling member 40 and the left side frame25L restrict the leftward movement of the left vertical plate 22L.Therefore, a reaction force for canceling out a component along thefight-left direction of the compression force is generated in the firstcoupling member 40, in a direction opposite to the direction of theblack arrow shown in FIG. 7. Consequently, the first coupling member 40and the left side frame 25L inhibit the left vertical plate 22L frombeing deformed.

Note that the first coupling member 40 according to the presentembodiment is provided for the purpose of preventing the left verticalplate 22L from being deformed. The first coupling member 40 therefore isstrong in the right-left direction and weak in the front-back direction.The first coupling member 40 of such a structure is different from thebeams 23 that are required to have a rigidity enhancing function. Forthis reason, a bracket or the like to which a high load is applied isnot joined to the first coupling member 40.

When joining the first coupling member 40 to the inclined part 32 of theleft vertical plate 22L, the first coupling member 40 needs to be joined(welded) to an inclined surface. This breaks the joined section easilyand pulls the first coupling member 40 before a load acts on the rearcurved part 35. Consequently, deformation of the left vertical plate 22Lcannot be prevented efficiently.

Furthermore, because the left vertical plate 22L deforms starting fromthe rear curved part 35, the effect of preventing the left verticalplate 22L from being deformed declines as the joined position betweenthe first coupling member 40 and the left vertical plate 22L separatesrearward from the rear curved part 35. It is considered optimal to jointhe first coupling member 40 to the rear curved part 35, but it isdifficult to steadily join the first coupling member 40 to the curvedsurface of the rear curved part 35 by welding or the like. It is,therefore, preferred that the first coupling member 40 be joined to aposition that is slightly behind the rear curved part 35. Thus, thefirst coupling member 40 according to the present embodiment is joinedto the position in the vicinity of the rear curved part 35 (the frontend part of the parallel part 33).

As described above, in the present embodiment the support parts 22 a forsupporting the attachment 9 are provided in front of the slewing bearing30. The left vertical plate 22L has the rear curved part 35 behind thesupport parts 22 a. Therefore, when the first coupling member 40according to the present embodiment is not provided, a load from theattachment 9 deforms the left vertical plate 22L in the direction inwhich the rear curved part 35 approaches the right vertical plate 22R(the direction in which the rear curved part 35 expands) and, at thesame time, swings the front part of the upper frame 5 around the slewingbearing 30. Therefore, it is difficult to steadily support theattachment 9. In the present embodiment, however, the first couplingmember 40 is provided for coupling the left side frame 25L and the leftvertical plate 22L to each other in order to prevent the left verticalplate 22L from being deformed in the direction in which the rear curvedpart 35 approaches the right vertical plate 22R. Therefore, even when alarge load applied from the attachment 9 to the support parts 22 a triesto deform the left vertical plate 22L in the direction in which the rearcured part 35 expands, the first coupling member 40 can prevent the leftvertical plate 22L from being deformed. Particularly, in the presentembodiment, the first coupling member 40 is connected to the left sideframe 25L that is provided with high rigidity in order to prevent theupper frame 5 from being deformed when a surrounding object collideswith the upper frame 5. Therefore, the load from the upper frame 5 canreliably be received by the left side frame 25L. Then, the front part ofthe bottom plate 21 can be prevented from swinging vertically around theslewing bearing 30, by preventing the left vertical plate 22L from beingdeformed. Consequently, the attachment 9 can be supported steadily.

In the present embodiment, the first coupling member 40 is fixed to anddisposed between the left vertical plate 22L and the left side frame 25Lthat is provided at the positions opposite to the right vertical plate22R with respect to the left vertical plate 22L. As a result, thecomponent along the right-left direction of the load transmitted fromthe attachment 9 to the left vertical plate 22L can reliably betransmitted to the left side frame 25L and the bottom plate 21 to whichthe left side frame 25L is fixed, via the first coupling member 40.Consequently, the left vertical plate 22L can be prevented from beingdeformed, not only in the direction in which the rear curved part 35approaches the right vertical plate 22R but also in the direction inwhich rear curved part 35 separates from the right vertical plate 22R.Thus, according to the present embodiment, the attachment 9 can besupported more steadily.

According to the present embodiment, the left vertical plate 22L caneffectively be prevented from being deformed by the load from theattachment 9. More specifically, the load applied from the attachment 9to the support part 22 a of the left vertical plate 22L acts mainly as atensile force on the inclined part 32 of the left vertical plate 22L.This tensile force is directed obliquely forward along the inclined part32. Because the component along the right-left direction of this tensileforce moves the rear curved part 35 toward the right vertical plate 22R,this component along the right-left direction needs to be received bythe left side frame 25L.

In the present embodiment, the first coupling member 40 is welded to theparallel part 33 of the left vertical plate 22L, so as to besubstantially perpendicular to the parallel part 33. Accordingly, thefirst coupling member 40 can be welded to the side surface of the leftvertical plate 22L (the parallel part 33) that extends perpendicular tothe component along the right-left direction of the tensile force. Thus,compared to when welding the first coupling member 40 to the sidesurface of the inclined part 32 that is inclined with respect to thefront-back direction, the welding strength with respect to the componentalong the right-left direction of the tensile force can be improved.Furthermore, in the present embodiment, the first coupling member 40 iswelded to the front end part of the parallel part 33. Because themovement of the left vertical plate 22L can be restricted in theposition closest to the rear curved part 35, the left vertical plate 22Lcan effectively be prevented from being deformed.

Furthermore, in the present embodiment, the first coupling member 40 isfixed to the parallel part 33 of the left vertical plate 22L, so as tobe substantially perpendicular to the parallel part 33, in other words,so as to be along the right-left direction. Accordingly, the componentalong the right-left direction of the tensile force can be firmlyreceived by the entirety of the first coupling member 40. Therefore, thefirst coupling member 40 can be made up by a simple member able toresist against the tensile force along the right-left direction.Specifically, the first coupling member 40 can be made up by a platemember whose thickness is arranged in the front-rear direction.

Note that even when the load applied from the attachment 9 to the leftvertical plate 22L acts as a compression force onto the inclined part 32of the left vertical plate 22L (a force directed obliquely rearward),the same effects can be realized.

The present embodiment further has the second coupling member 26 b forcoupling the inclined part 32 of the left vertical plate 22L and theright vertical plate 22R to each other. Therefore, while the firstcoupling member 40 holds the position of the parallel part 33 in theleft vertical plate 22L, the second coupling member 26 b holds theposition of the inclined part 32 in the left vertical plate 22L. In thismanner, the left vertical plate 22L can effectively be prevented frombeing deformed.

In the present embodiment, the left side frame 25L is formed from atubular member. Thus, bending strength of the left side frame 25L can beimproved. Therefore, the load from the attachment 9 can reliably bereceived by the left side frame 25L.

In the present embodiment as shown in FIG. 4, the section in the leftside frame 25L to which the first coupling member 40 is connected has agreater height than the section in the left vertical plate 22L to whichthe first coupling member 40 is connected. Thus, compared to when theleft side frame 25L has a smaller height than the left vertical plate22L, the bending strength of the left side frame 25L can be improved.Consequently, the load from the attachment 9 can reliably be received bythe left side frame 25L.

The operating machine according to the present invention comprises notonly the embodiment described above but also various otherconfigurations.

The embodiment described above employs the plate-like first couplingmember 40, but a first coupling member 40 of a rod shape for couplingthe upper part of the left vertical plate 22L and the left side frame25L to each other as shown in FIG. 8, may be employed. In other words,it is sufficient that the first coupling member 40 be joined (welded) toat least the upper part of the left vertical plate 22L. Thereby, theleft vertical plate 22L can be prevented from being deformed.Specifically, because a lower part of the left vertical plate 22L isfixed to the bottom plate 21, mainly the upper part of the left verticalplate 22L becomes deformed. The left vertical plate 22L can be preventedfrom being deformed, by coupling at least the upper part of the leftvertical plate 22L and the left side frame 25L to each other by means ofthe first coupling member 40, as shown in FIG. 8.

Moreover, the cross-sectional shape of the first coupling member 40 alsocan be selected appropriately from various shapes such as a circularshape, a rectangular shape, and the like. In other words, thecross-sectional shape of the first coupling member 40 can be selectedfrom cross-sectional shapes having tensile force capable of preventingthe left vertical plate 22L from being deformed.

The first coupling member 40 may have rigidity enough to be able tofunction as a beam. For instance, the cross section of the firstcoupling member 40 can be formed into an L shape or U shape.

The first coupling member 40 according to the present embodiment isfixed in a manner as to be substantially perpendicular to the left sideframe 25L and the parallel part 33 of the left vertical plate 22L.However, the first coupling member 40 may be fixed in a manner as to beinclined with respect to the left side frame 25L and the left verticalplate 22L. For example, the first coupling member 40 may be fixed to theleft side frame 25L and the left vertical plate 22L so as to extendsubstantially parallel to the inclined part 32.

Additionally, the configurations of the vertical plates 22 may bereversed right and left. A curved part may be formed, not only on theleft vertical plate 22L but also on the right vertical plate 22R. Whencurved parts are formed in both of the vertical plates 22, the firstcoupling member 40 can be provided between the right vertical plate 22Rand the right side frame 25R as well.

The operating machine according to the present embodiment is not limitedto the hydraulic shovel 1 shown in FIG. 1. The configuration describedabove can be adopted to a so-called swing type hydraulic shovel in whichthe attachment 9 is supported so as to be able to swing in theright-left direction with respect to the support parts 22 a.

Inventions with the following configurations are mainly included in thespecific embodiment described above.

In other words, the present invention provides an upper slewing bodythat is provided on a lower propelling body of an operating machine soas to be able to slew, the upper slewing body comprising: an upper framethat has a bottom plate that is supported on the lower propelling bodyvia a slewing bearing so as to be able to slew, first and secondvertical plates that are provided to stand on the bottom plate so as toface each other in a right-left direction and to extend in a front-backdirection, and a side frame fixed to the bottom plate and configuring apart of a rim part of the upper frame, the vertical plates each having asupport part located in front of the slewing bearing; and an attachmentthat is supported on the support parts of the vertical plates so as tobe able to rise and fall, wherein the first vertical plate has a curvedpart, behind the support part, which is curved to form a convex shapedirected toward an opposite side of the second vertical plate in aplanar view, and the upper slewing body further comprises a firstcoupling member for coupling the side frame and the first vertical plateto each other so as to prevent the first vertical plate from beingdeformed in a direction in which the curved part approaches the secondvertical plate.

According to the present invention, the first vertical plate has thecurved part that is curved into a convex shape directed toward theopposite side of the second vertical plate in the rear of the supportpart. The upper slewing body according to the present invention has thefirst coupling member that couples the side frame and the first verticalplate to each other so as to prevent the first vertical plate from beingdeformed in a direction in which the curved part approaches the secondvertical plate in a planar view.

In the upper slewing body according to the present invention, thesupport part supporting the attachment is provided in front of theslewing bearing. Further, the first vertical plate has a curved partbehind the support part. Therefore, when the first coupling memberaccording to the present invention is not provided, a load from theattachment deforms the first vertical plate in the direction in whichthe curved part approaches the second vertical plate (the direction inwhich the curved part expands) and, at the same time, swings verticallythe front part of the upper frame around the slewing bearing. Therefore,it is difficult to steadily support the attachment. In the presentinvention, however, the first coupling member is provided for couplingthe side frame and the first vertical plate to each other in order toprevent the first vertical plate from being deformed in the direction inwhich the curved part approaches the second vertical plate. Therefore,even when the application of a large load from the attachment to thesupport part tries to deform the first vertical plate in the directionin which the cured part expands, the first coupling member can preventthe first vertical plate from being deformed. Particularly, in thepresent invention, the first coupling member is connected to the sideframe that is provided with high rigidity in order to prevent the upperframe from being deformed when a surrounding object collides with theupper frame. Therefore, the load from the upper frame can reliably bereceived by the side frame. Then, the front part of the bottom plate canbe prevented from swinging vertically around the slewing bearing, bypreventing the first vertical plate from being deformed. Consequently,the attachment can be supported steadily.

It is preferred that, in the upper slewing body, the side frame beprovided at a position opposite to the second vertical plate withrespect to the first vertical plate, and that the first coupling memberbe fixed to and disposed between the side frame and the first verticalplate.

In this aspect, the first coupling member is fixed to and disposedbetween the first vertical and the side frame plate that is provided atthe positions opposite to the second vertical plate with respect to thefirst vertical plate. In this manner, the component along right-leftdirection of the load transmitted from the attachment to the firstvertical plate can reliably be transmitted to the side frame and thebottom plate to which the side frame is fixed, via the first couplingmember. Consequently, the first vertical plate can be prevented frombeing deformed, not only in the direction in which the curved partapproaches the second vertical plate but also in the direction in whichcurved part separates from the second vertical plate. Thus, according tothis aspect, the attachment can be supported more steadily.

It is preferred that, in the upper slewing body, the first verticalplate include a curved rear part extending rearward from the curved partand a curved front part extending forward from the curved part in amanner that the curved front part comes closer to the second verticalplate toward the front direction, and that the first coupling member bewelded to a front end part of the curved rear part so as to besubstantially perpendicular to the curved rear part of the firstvertical plate.

According to this aspect, the first vertical plate can effectively beprevented from being deformed by the load from the attachment. Morespecifically, the load applied from the attachment to the support partof the first vertical plate acts mainly as a tensile force onto thecurved front part of the first vertical plate. This tensile force isdirected obliquely forward along the curved front part. Because thecomponent of this tensile force along right-left direction moves thecurved part toward the second vertical plate, this component alongright-left direction needs to be received by the side frame.

In this aspect, the first coupling member is welded to the curved rearpart of the first vertical plate so as to be substantially perpendicularto the curved rear part. Accordingly, the first coupling member can bewelded to the side surface of the first vertical plate (the curved rearpart) that extends perpendicular to the component of the tensile forcealong right-left direction. Thus, compared to when welding the firstcoupling member to the side surface of the curved front part that isinclined with respect to the front-back direction, the welding strengthwith respect to the component of the tensile force along right-leftdirection can be improved. Furthermore, in this aspect, the firstcoupling member is welded to the front end part of the curved rear part.Because the movement of the first vertical plate can be restricted inthe position closest to the curved part, the first vertical plate caneffectively be prevented from being deformed.

Furthermore, in this aspect, the first coupling member is welded to thecurved rear part of the first vertical plate so as to be substantiallyperpendicular to the curved rear part, in other words, so as to be alongthe right-left direction. Accordingly, the right-left component of thetensile force can be firmly received by the entirety of the firstcoupling member. Therefore, the first coupling member can be made up bya simple member able to resist against the tensile force alongright-left direction. For example, the first coupling member can be madeup by a plate member whose thickness is arranged in the front-backdirection.

Note that even when the load applied from the attachment to the firstvertical plate acts as a compression force onto the curved front part ofthe first vertical plate (a force directed obliquely rearward), the sameeffects can be realized.

It is preferred that the upper slewing body further have a secondcoupling member for coupling the curved front part of the first verticalplate and the second vertical plate to each other so as to prevent thefirst vertical plate from being deformed in a direction in which thecurved part approaches the second vertical plate and a direction inwhich the curved part separates from the second vertical plate.

In this aspect the upper slewing body further has the second couplingmember for coupling the curved front part of the first vertical plateand the second vertical plate to each other. Therefore, while the firstcoupling member holds the position of the curved rear part of the firstvertical plate, the second coupling member can hold the position of thecurved front part of the first vertical plate. In this manner, the firstvertical plate can effectively be prevented from being deformed.

It is preferred that, in the upper slewing body, the side frame beformed from a tubular member that has a circumferential wall provided ina range of the entire circumference around an axis along a longitudinaldirection of the side frame, and that the first coupling member be fixedto the circumferential wall of the side frame.

In this aspect, the side frame is formed from a tubular member. Thus,bending strength of the side frame can be improved. Therefore, the loadfrom the attachment can reliably be received by the side frame.

It is preferred that, in the upper slewing body, the section in the sideframe to which the first coupling member is connected have a greaterheight than the section in the first vertical plate to which the firstcoupling member is connected.

In this aspect, the side frame has a greater height than the firstvertical plate. Thus, compared to when the side frame has a smallerheight than the first vertical plate, the bending strength of the sideframe can be improved. Consequently, the load from the attachment canreliably be received by the side frame.

In the upper slewing body, it is sufficient that the first couplingmember be fixed to at least an upper part of the first vertical plate.

According to this aspect, the first vertical plate can be prevented frombeing deformed. Specifically, because a lower part of the first verticalplate is fixed to the bottom plate, mainly the upper part of the firstvertical plate becomes deformed. Therefore, the first vertical plate canbe prevented from being deformed, by coupling at least the upper part ofthe first vertical plate and the side frame to each other by means ofthe first coupling member.

The present invention also provides an operating machine that has theupper slewing body described above and a lower propelling body thatsupports the upper slewing body via the slewing bearing so as to allowthe upper slewing body to slew.

This application is based on Japanese Patent application No. 2011-227224filed in Japan Patent Office on Oct. 14, 2011, the contents of which arehereby incorporated by reference.

Although the present invention has been fully described by way ofexample with reference to the accompanying drawings, it is to beunderstood that various changes and modifications will be apparent tothose skilled in the art. Therefore, unless otherwise such changes andmodifications depart from the scope of the present invention hereinafterdefined, they should be construed as being included therein.

What is claimed is:
 1. An upper slewing body that is provided on a lowerpropelling body of an operating machine so as to be able to slew, theupper slewing body comprising: an upper frame that has a bottom platethat is supported on the lower propelling body via a slewing bearing soas to be able to slew, first and second vertical plates that areprovided to stand on the bottom plate so as to face each other in aright-left direction and to extend in a front-back direction, and a sideframe fixed to the bottom plate and configuring a part of a rim part ofthe upper frame, the vertical plates each having a support part locatedin front of the slewing bearing; and an attachment that is supported onthe support parts of the vertical plates so as to be able to rise andfall, wherein the first vertical plate has a curved part, behind thesupport part, which is curved to form a convex shape directed toward anopposite side of the second vertical plate in a planar view, and theupper slewing body further comprises a first coupling member forcoupling the side frame and the first vertical plate to each other so asto prevent the first vertical plate from being deformed in a directionin which the curved part approaches the second vertical plate.
 2. Theupper slewing body according to claim 1, wherein the side frame isprovided at a position opposite to the second vertical plate withrespect to the first vertical plate, and the first coupling member isfixed to and disposed between the side frame and the first verticalplate.
 3. The upper slewing body according to claim 2, wherein the firstvertical plate includes a curved rear part extending rearward from thecurved part and a curved front part extending forward from the curvedpart in a manner that the curved front part comes closer to the secondvertical plate toward the front direction, and the first coupling memberis welded to a front end part of the curved rear part so as to besubstantially perpendicular to the curved rear part of the firstvertical plate.
 4. The upper slewing body according to claim 3, furthercomprising a second coupling member for coupling the curved front partof the first vertical plate and the second vertical plate to each otherso as to prevent the first vertical plate from being deformed in adirection in which the curved part approaches the second vertical plateand a direction in which the curved part separates from the secondvertical plate.
 5. The upper slewing body according to claim 1, whereinthe side frame is formed from a tubular member that has acircumferential wall provided in a range of the entire circumferencearound an axis along a longitudinal direction of the side frame, and thefirst coupling member is fixed to the circumferential wall of the sideframe.
 6. The upper slewing body according to claim 1, wherein a sectionin the side frame to which the first coupling member is connected has agreater height than a section in the first vertical plate to which thefirst coupling member is connected.
 7. The upper slewing body accordingto claim 1, wherein the first coupling member is fixed to at least anupper part of the first vertical plate.
 8. An operating machine thathas: the upper slewing body according to claim 1, and a lower propellingbody that supports the upper slewing body via the slewing bearing so asto allow the upper slewing body to slew.